Tone hole cups are that part of a wind instrument which cover the tone holes. Musical instruments such as flutes are available in two varieties, closed hole (also called the "American" style) and open hole or "French" cup style. The French or open hole style (i.e., cups with holes in them) are often preferred by more advanced musicians who perform "half holing", an advanced playing technique. Musicians who are beginning to learn this advanced technique often use removable open hole cup plugs which fit in the open hole cups and seal the open hole. When the musician wishes to practice more advanced techniques, he or she removes the plugs.
The use of removable open hole cup plugs is also advantageous from an inventory and cost standpoint, since a flute manufacturer can sell open hole cup flutes in combination with a set of plugs, and then the consumer can use the flute either as a closed hole cup style flute or as a French, open hole cup style flute.
In the prior art, the open hole cup plugs were typically made of either cork or silicone. There are several disadvantages associated with these types of plugs.
First, they are not very aesthetically pleasing. A high quality flute can be quite expensive and a silicone or cork open hole cup plug can seriously detract from the overall high quality appearance of the flute.
Second, in high quality flutes and other wind instruments, the goal is to achieve a certain resonance and pitch of each tone hole via quality cup pad materials precisely oriented in the cups. See U.S. Pat. Nos. 5,183,954 and 5,339,719 incorporated herein by this reference. But, cork and silicone open cup hole plugs have been found to adversely affect the resonance qualities of the musical instrument.
Third, in the prior art, there are no convenient means for storing the plugs and thus they were often lost or misplaced. Contributing to this fact is that in order to remove a cork or silicone plug, the musician is required to push the plug down through the tone hole and then shake the plug out of the end of the musical instrument.